JPH05197034A - Device for preventing erroneous lighting of copying lamp - Google Patents

Abstract

PURPOSE:To prevent a copying lamp from being continuously lighted by forcibly stopping the supply of power source to the copying lamp by judging that the copying lamp is erroneously lighted when a current flows in the copying lamp at the time of standby. CONSTITUTION:The input state from a control panel 9 and the detecting states of respective sensors are inputted in a main control circuit 2. The respective loads of a copying lamp control circuit 1, a motor for moving an optical system 7, and a main motor 8, etc., are connected to the main control circuit 2. Then, a current detection circuit 10 detects the current flowing in the copying lamp 5 and outputs the detected result to a main control circuit 2. In the case of detecting the current flowing in the copying lamp 5, an unlighted state is known when a lighted state is not detected. In the case that the copying lamp is lighted when a driving signal is not outputted to the motor 7 from the circuit 2, the copying lamp 5 is turned off by judging that the copying lamp is erroneously lighted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for controlling a copy lamp for exposing a document in a copying machine, and more particularly to an apparatus for preventing false lighting of a copy lamp for preventing heat generation due to false lighting of the copy lamp.

[0002]

2. Description of the Related Art In a copying machine equipped with a copy lamp for exposing a copy document, an abnormality occurs in the lighting system of the copy lamp due to a malfunction of the CPU, line damage, etc., and the copy lamp is kept lit. There is. Therefore, in order to deal with such an abnormality in the conventional copy lamp control system, a temperature fuse is provided in the reflector, and the power supply to the copy lamp is forcibly stopped at the time of an abnormality due to the melting of the temperature fuse, and in the worst case of a fire or the like. It prevented the occurrence of trouble.

[0003]

However, the temperature around the copy lamp has risen to some extent by the time the thermal fuse is blown, and the adverse effect on the photoconductor is inevitable, and the exterior made of resin is used. There was a possibility of deformation and smoke. Therefore, it is not desirable that the method of detecting the abnormal lighting of the copy lamp is only the thermal fuse, and it has been desired to detect the abnormal lighting of the copy lamp by another method before the thermal fuse is blown.

An object of the present invention is to prevent the false lighting of a copy lamp by monitoring whether or not the conditions for false lighting of the copy lamp are satisfied, so that the copy lamp can be turned off before the temperature around the copy lamp abnormally rises. To provide.

[0005]

FIG. 1 is a diagram showing the configuration of the present invention. When the current flowing through the copy lamp is detected in the copy standby state, the copy lamp off signal is output and the power supply to the copy lamp is stopped.

[0006]

The copy lamp is only required to be turned on during scanning of the original, that is, during the copying process, and should be turned off during the standby for copying. conventionally,
The copy lamp lit up even while waiting for copying, causing problems such as abnormal temperature rise and smoking. According to the present invention, the power supply to the copy lamp is forcibly stopped when a current is flowing through the copy lamp during the copy standby, so that the above problem does not occur.

[0007]

FIG. 2 is a block diagram of essential parts of a copying machine according to an embodiment of the present invention.

The copying machine is provided with a main control circuit 2, and a CPU 11 therein controls the entire copying machine. The input state from the operation panel 9 and the detection state of each sensor are input to the main control circuit 2. The main control circuit 2 is connected to the copy lamp control circuit 1, the optical system moving motor 7, the main motor 8 and other loads.

The copy lamp control circuit 1 is a circuit for performing lighting control of a copy lamp for exposing a copy document by known phase control, and a copy lamp 5, a temperature fuse 6, and a current detection circuit 10 are connected in series. Current detection circuit 10
Detects the current flowing through the copy lamp 5 and outputs the detection result to the main control circuit 2. When the current flowing through the copy lamp 5 is detected, it can be known that the copy lamp 5 is in the lit state, and when the current is not detected, it can be known that it is in the off state. The copy lamp 5 is turned on by the phase control of the copy lamp control circuit 1 using the AC power supply 4 as a power source. This AC power supply 4
A power relay 3 is connected to the power relay 3 and the power relay 3 is on / off controlled by the main control circuit 2.

An optical system moving motor 7 is a motor for moving the copy lamp 5 along a document table (not shown), and a copying machine main body driving motor 8 operates other driving systems such as a photoconductor (rotation etc.). It is a motor for driving.

When a normal copy process is performed, the copy lamp 5 is turned on, and along with this, the optical system moving motor 7
Is driven and the copy lamp 5 scans the original. And
When the document scanning is completed, the copy lamp 5 is turned off and the optical system moving motor 7 is stopped. From this, the copy lamp 5 should be off when the optical system moving motor 7 is stopped. Therefore, when the optical system moving motor 7 is stopped, that is, when the drive signal is not output from the main control circuit 2 to the optical system moving motor 7, the copy lamp 5 is turned on ( (When current is flowing in the copy lamp circuit)
The copy lamp 7 is turned off when it is determined that the lamp is erroneously lit.

FIG. 3 is a flow chart showing the processing procedure of the main part of the copying machine.

During the copying process, the main body driving motor 8 and the optical system moving motor 7 operate to feed the copy lamp 5 (n1 → n2). The copy lamp 5 is phase-controlled to expose a document with a predetermined light amount, and during that time, image data is taken in (n3 → n4 → n).
5 → n6). When the current value flowing through the copy lamp 5 is not detected even while the document is being scanned, it is determined that an abnormality has occurred in the copy lamp 5, the power relay 3 is turned off, and the operation panel 9 on the copying machine main body has a trouble. Is displayed (n3 → n12 → n13). This abnormality is, for example, a copy lamp burnout.

When the document scanning is completed, the copy lamp 5 is turned off and the process is returned (n7). here,
If the CPU malfunctions or the line is damaged, the copy lamp 5
If is not turned off, the optical system moving motor 7,
The copy lamp lights up even though the motor 8 for moving the copying machine body is stopped (in the copy standby state),
A current will flow through the copy lamp 5. Therefore, even though the motor 7 etc. are stopped, the copy lamp 5
When a current flowing through the power source is detected, the power relay 3 is turned on to forcibly stop the copy lamp 5, and the operation panel 9 displays that a trouble has occurred to inform the user of the occurrence of the trouble ( n8 → n1
1 → n12 → n13). When all the copies have been completed, the drive motor of the main body of the copying machine is stopped (n9 → n).
10).

[0015]

According to the present invention, the copy lamp is turned on during the standby of the copy process, that is, if current is flowing through the copy lamp, it is determined that the copy lamp is erroneously turned on, and the power is forcibly supplied to the copy lamp. Since it is stopped, it is possible to prevent the copy lamp from continuing to light during the copy standby.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of the present invention.

FIG. 2 is a block diagram showing a main configuration of a copying machine according to the present invention.

FIG. 3 is a flowchart relating to copy lamp control of the copying machine.

Claims (1)

[Claims] 1. A copy lamp current detecting means for detecting a current flowing through a copy lamp for scanning an original, and a means for stopping a power supply to the copy lamp when the current is detected in a copy standby state. A mistaken lighting prevention device for the copy lamp.